Title: Error messages when activating
Last modified: September 18, 2018

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# Error messages when activating

 *  Resolved [ssimo3](https://wordpress.org/support/users/ssimo3/)
 * (@ssimo3)
 * [7 years, 8 months ago](https://wordpress.org/support/topic/error-messages-when-activating/)
 * Hello:
    I am running WordPress 4.9.8 on a Windows machine. I am getting the following
   error when I activate the WordPress MooTools Tree Creator plugin:
 * The plugin generated 360 characters of unexpected output during activation. If
   you notice “headers already sent” messages, problems with syndication feeds or
   other issues, try deactivating or removing this plugin.
 * [Click here for screenshot](https://www.dropbox.com/s/wjkqef6qo9rw7eb/Plugins%20%E2%80%B9%20LSUHSC%20HDC%20Test%20WordPress%20%E2%80%94%20WordPress.png?dl=0)
 * Additionally, the following warning appears in all WP_Admin screens, no matter
   whether WP_DEBUG is true or false:
 *  Warning: Declaration of Mootree_walker::start_el(&$output, $page, $depth, $args,
   $current_page = 0) should be compatible with Walker_Page::start_el(&$output, 
   $page, $depth = 0, $args = Array, $current_page = 0) in C:\Bitnami\wordpress-
   4.9.8-0\apps\wordpress\htdocs\wp-content\plugins\wp-moo-tree\tree-shortcode.php
   on line 0
 * This plugin is causing degradation of basic functionality of WordPress. For instance,
   the items in the Media Library do not show:
 * [Click here for screenshot](https://www.dropbox.com/s/jddweyqfn4wvr3u/Media%20Library%20%E2%80%B9%20LSUHSC%20HDC%20Test%20WordPress%20%E2%80%94%20WordPress.png?dl=0)
 * There is no error message output to my browser console; the media files simply
   do not show.
 * I’m not sure whether this is one bug or many, as I’m not sure they’re related.
   I’m guessing that they are. But I have tried deactivating every other plugin 
   on my site, and both these problems persist.

Viewing 1 replies (of 1 total)

 *  Plugin Author [aryanduntley](https://wordpress.org/support/users/dunar21/)
 * (@dunar21)
 * [7 years, 8 months ago](https://wordpress.org/support/topic/error-messages-when-activating/#post-10699752)
 * I do not update this plugin anymore. If it’s breaking you should not use it. 
   When I have the time, I’ll Put a notice that it’s no longer compatible with newer
   version of WP, or remove it if I can. I’m pretty sure I do not want to update
   it.
    -  This reply was modified 7 years, 8 months ago by [aryanduntley](https://wordpress.org/support/users/dunar21/).

Viewing 1 replies (of 1 total)

The topic ‘Error messages when activating’ is closed to new replies.

 * ![](https://s.w.org/plugins/geopattern-icon/wp-moo-tree_1f7cb8.svg)
 * [Wordpress MooTools Tree Creator](https://wordpress.org/plugins/wp-moo-tree/)
 * [Frequently Asked Questions](https://wordpress.org/plugins/wp-moo-tree/#faq)
 * [Support Threads](https://wordpress.org/support/plugin/wp-moo-tree/)
 * [Active Topics](https://wordpress.org/support/plugin/wp-moo-tree/active/)
 * [Unresolved Topics](https://wordpress.org/support/plugin/wp-moo-tree/unresolved/)
 * [Reviews](https://wordpress.org/support/plugin/wp-moo-tree/reviews/)

## Tags

 * [media](https://wordpress.org/support/topic-tag/media/)

 * 1 reply
 * 2 participants
 * Last reply from: [aryanduntley](https://wordpress.org/support/users/dunar21/)
 * Last activity: [7 years, 8 months ago](https://wordpress.org/support/topic/error-messages-when-activating/#post-10699752)
 * Status: resolved